Field
The present disclosure relates generally to bandwidth provisioning in a wireless communication system. More specifically, the present disclosure relates to dynamic bandwidth provisioning across multiple Long-Term Evolution (LTE) channels.
Related Art
In the past decade, LTE (also known as 4G LTE) has been replacing the third generation (3G) technology as the current mobile telecommunications technology. It is developed from the GSM (Global System for Mobile Communications)/UMTS (Universal Mobile Telecommunications System) technology. By using new DSP (digital signal processing) techniques and modulations, LTE can increase the capacity and speed of wireless data networks.
According to 3GPP (3rd Generation Partnership Project), the group that develops the LTE standard, the motivations for LTE include the user demand for higher data rates and quality of service, the continued demand for cost reduction (in both capital expenditures and operational expenditures), and the need to avoid unnecessary fragmentation of technologies for paired and unpaired band operation.
The main requirements of the LTE networks are high spectral efficiency, high peak data rates, and short round trip time, as well as flexibility in frequency and bandwidth. More specifically, to achieve high radio spectral efficiency as well as to enable efficient scheduling in both the time and frequency domains, LTE uses a multicarrier approach for multiple access, such as Orthogonal Frequency Division Multiple Access (OFDMA). OFDMA is a multicarrier technology subdividing the available bandwidth into a multitude of mutual orthogonal narrowband subcarriers, which can be shared among multiple users. In LTE, both the downlink and the uplink can dynamically assign radio resources to meet different users' traffic requirements. The minimum radio resource described in the LTE standard is called a resource block (RB), which consists of 12 consecutive subcarriers, or 180 kHz, for the duration of one slot (7 symbols or 0.5 ms).
To enable possible deployment around the world, supporting as many regulatory requirements as possible, LTE is developed for a number of frequency bands, ranging from 700 MHz up to 2.7 GHz. The available bandwidths are also flexible, including 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz. In LTE, in order to increase the bandwidth, hence the bitrate, allocated to a user, multiple (up to five) channels can be aggregated, known as carrier aggregation. When carrier aggregation is used, a user can be allocated resources on any one of the aggregated channels.
Although able to increase available bandwidth provisioned to a user, LTE carrier aggregation does not work for systems where available resources are scattered among different logical channels and when user needs may change dynamically.